I am going to use a marine gen. My initial plan was to remove the heat exchanger since there will not be an unlimited supply of salt water. Is is feasable to run the domestic water on it's way to the water heater through the exchanger? In theory, it would pre heat the water when the gen is running.

Yes in theory, you're right-it will heat the water. But remember, there have been years of guck running through the system, along with most likely cast iron surrounds. The better way is to run a coolant loop through the water heater with copper piping. I'd suggest completely getting rid of the marine stuff and convert it back to what it was originally before it became a marine generator. Use a remote radiator with a belt driven squirrel cage blower (belt driven can run slower-and be quieter than a direct drive blower) and both you and your neighbors will be the happiest with the very quiet generator. Good Luck, TomC

I wonder, If you pipe the genset radiator through your H2O heater, than through your hydronic coil for the HPs , than anything else you have planned,before sending that water to your radiator. If thats a good idea or not! Boy, my thoughts are using simple bypass valves to utilitize this option any timeyou want extra heat while you are running your gen. anyway! Whats Your Thoughts?